Wednesday, April 24, 2013

Saber Toothed Tiger

Saber-toothed cat

A saber-toothed cat (alternatively spelled sabre-toothed cat),[1] also known as a saber-toothed tiger,[2][3] is any of various groups of predatory mammals related to modern cats (or resembling cats) that were characterized by long, sabre-shaped canine teeth. These animals belonged to subfamilies of Machairodontinae (Felidae), Barbourofelidae and Nimravidae (both Feliformia) as well as two families related to marsupials that were found worldwide from the Eocene Epoch to the end of the Pleistocene Epoch (42 mya—11,000 years ago), existing for approximately 42 million years.[4][5][6] The large maxillary canine teeth extended from the mouth even when it was closed. Despite the name, not all animals known as saber-toothed cats were closely related to modern felines.
The Nimravidae are the oldest, entering the landscape around 42 mya and becoming extinct by 7.2 mya. Barbourofelidae entered around 16.9 mya and were extinct by 9 mya. These two would have shared some habitats.

Contents

Morphology

These subfamilies evolved their saber-toothed characteristics entirely independently. They are most known for having maxillary canines
which were, in some species, up to 50 cm (19.7 inches) long and
extended down from the mouth even when the mouth was closed.
Sabre-toothed cats were generally more robust than today's cats and were
quite bear-like in build. They were believed to be excellent hunters
and hunted animals such as sloths, mammoths, and other large prey. Evidence from the numbers found at La Brea Tar Pits suggests that Smilodon, like modern lions, was a social carnivore.[7]
The first late saber-tooth instance is a group of animals ancestral to mammals but not yet mammals. Known as synapsids
or mammal-like reptiles, they were one of the first groups of animals
to experiment with specialization of teeth and many had long canines.
Some had two pairs of upper canines with two jutting down from each
side, but most had one pair of upper extreme canines. Because of their
primitiveness, they are extremely easy to tell from machairodonts. With
no cononoid process, many sharp "premolars" more like pegs than
scissors, a very long, lizard-like head are among several things that
mark them out.
The second appearance of long canines is Thylacosmilus. Thylacosmilus
is the most unique of the saber-tooth mammals and is also easy to tell
apart. It differs from machairodonts in a possessing a very prominent
flange and a tooth that is triangular in cross section. The root of the
canines is more prominent than in machairodonts and a true sagittal crest is absent.
The third instance of saber teeth is from order Creodonta. The small and slender Machaeroides bore canines that were thinner than in the average machairodont. Its muzzle was longer and narrower.
The fourth saber-tooth appearance is the ancient family of carnivores, the nimravids
and they are notoriously hard to tell apart from machairodonts. Both
groups have short skulls, tall sagittal crests, and the general skull
shape is very similar. Some have distinctive flanges, some have none at
all, so this confuses the matter further. Machairodonts were almost
always bigger, though, and their canines were longer and more stout for
the most part, but exceptions do appear.
The fifth appearance is the barbourofelids. These carnivores are very
closely related to actual cats, and as such, they are hard to tell
apart. The best known barbourofelid is Barbourofelis, which differs from most machairodonts by a mandible that is much heavier and more stout, smaller orbits,
massive and almost knobby flanges, and canines that are farther back.
The average machairodont has well-developed incisors, but barbourofelids
were more extreme.
The sixth and last of the sabertooth group to evolve were the machairodonts themselves.

Prey

Steps of reconstruction

Many of the extinct subfamilies of the saber-toothed cats' food
source were large mammals such as elephants, rhinos, and other colossal
herbivores of the era. The evolution of enlarged canines in Tertiary
carnivores was a result of large mammals being the source of prey for
saber-toothed cats. The development of the saber-toothed condition
appears to represent a shift in function and killing behavior, rather
than one in predator-prey relations. There are many hypotheses
concerning saber-tooth killing methods, some of which include attacking
soft tissue such as the belly and throat, where biting deep was
essential to generate killing blows. The elongated teeth also aided with
strikes reaching major blood vessels in these large mammals. However,
the precise functional advantage of the saber-toothed cat's bite,
particularly in relation to prey size, is a mystery. A new
point-to-point bite model is introduced in the article by Andersson et
al., showing that for saber-tooth cats, the depth of the killing bite
decreases dramatically with increasing prey size. The extended gape of
saber-toothed cats results in a considerable increase in bite depth when
biting into prey with a radius of less than 10 cm. For sabre-tooth,
this size-reversed functional advantage suggests predation on species
within a similar size range to those attacked by present-day
carnivorans, rather than "mega herbivores" as previously believed.
Some scientists say that the name of the cat is actually misleading.
The large canines did indeed distinguish the cat from others, but when
it came to hunting prey, it was the strong front limbs of the cat that
got the job done. These strong muscles held down the prey while the cat
then attempted to bite into the meat. This reason is why many scientists
argue that it was the incredibly strong front limbs that truly
distinguished the cat from the rest. The power of the front limbs should
not be overlooked, especially since they were one of a kind on such a
creature. Regardless, the cat was at the top of the food chain due to
the combined power of both the extended teeth, which helped tear up and
eat the meat, and the strong limbs.
A disputing view of the cat’s hunting technique and ability is
presented by C.K. Brain in “The Hunters or the Hunted?” in which he
attributes the cats’ neck muscles for its ability at killing large prey.
Large cats use both the upper and lower jaw to bite down and bring down
the prey. The strong bite of the jaw is accredited to the strong
temporalis muscle that attach from the skull to the coronoid process of
the jaw. The larger the coronoid process, the larger the muscle that
attaches there and therefore the stronger the bite. As C.K. Brain points
out, the saber-toothed cats had a greatly reduced coronoid process and
therefore a disadvantageously weak bite. The cat did however have an
enlarged mastoid process, a muscle attachment at the base of the skull,
which attaches to neck muscles. According to C.K. Brain the saber-tooth
would use a “downward thrust of the head, powered by the neck muscles”
to drive the large upper canines into the prey. This technique was “more
efficient than those of true cats”.

Ecology

Why does the adaptation of saber-like canines come about at least
four different times in different families such as nimravids,
marsupials, and felids? The similarity in all these unrelated families
involves convergent evolution of the saber-like canines as a hunting
adaptation. Meehan et al. note that it took approximately 8
million years for a new type of saber-toothed cat to fill the niche of
an extinct predecessor in a similar ecological role; this has happened
at least four times with different families of animals developing this
adaptation. Although the adaptation of the saber-like canines made these
creatures successful, it seems that the shift to obligate carnivorism, along with co-evolution
with large prey animals, led the saber-toothed cats of each time period
to extinction. As per Van Valkenburgh, the adaptations that made
saber-toothed cats successful also made the creatures vulnerable to
extinction. In her example, trends toward an increase in size, along
with greater specialization, acted as a "macro-evolutionary ratchet":
when large prey became scarce or extinct, these creatures would be
unable to adapt to smaller prey, consume other sources of food, and
would be unable to reduce their size so as to need less food. The
adaptations that would bring these creatures to apex predator status and dominance would lead them to their evolutionary doom.

Saber-tooth evolutionary tree

All saber-tooth mammals lived between 33.7 million and 9,000 years
ago, but the evolutionary lines that led to the various saber-tooth
genera started to diverge much earlier. It is thus a polyphyletic grouping.
The lineage that led to Thylacosmilus was the first to split off, in the late Cretaceous. It is a marsupial, and thus more closely related to kangaroos and opossums than the felines. The creodonts diverged next, and then the nimravids, before the blossoming of the truly feline saber-tooths.

^Pool, Bob (September 16, 2012). "What Is A Sabertooth". UC Berkeley. Retrieved 2012-06-12.
"I remember reading about this as a kid. I can still remember seeing a
picture of the saber-toothed tiger struggling in the tar"

^"What Is a Sabertooth?". University of California Museum of Paleontology. December 2005. Retrieved 2012-06-12. "The name "saber-toothed tiger" is misleading as these animals are not closely related to tigers."

ONLY ACCEPTABLE free Court-Judge Procedure in Canada - ORDER OF PEACE = Peace Bomd - And nothing else as to "inquisition-torture" mental health detentions...! The Suprme Civil Court does not have forms for a Peace Bond and the Police R.C.M.P. do not either...! Allegedly the Provincial Courts in Civil or Penal...!

For you are a jolly "good" fellow, and "nobody" and "you" can deny that...! - http://surrey.rcmp-grc.gc.ca - http://www.fraserhealth.ca/your_care/mental-health-and-substance-use/ ; "CAGED" humans as in a Zoo[even in the City or houses], with most needs met, with the rights of animals, no defense, behave better...! YOU BET...! Let them go, and you will get a "stampede", as good animals...!

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A trip in time at Wonder_land - From Surrey to Downtown and Intl. Aprt. Vancouver [YVR]

I HAVE COMPLETELY WALKED AND TRAMPLED anywhere their "Jesus" walked, and where all Government of Canada has walked! The dust of the trails of their brutal minds and dumb logic! Their slavery of peasants and all of us! At both YVR-Vancouver Airport National and International Terminal...! THEY ARE A DISGRACE!
Thanks to the NDP we have Universal Health Care and the English who give support though meager! Otherwise we would be a BANANA republic!
I WILL EXPLAIN SOON WHY THEY ARE FEUDALISTIC! You could loose an eye, a hand, an arm, or a leg! You already loose your teeth, as it is too costly to repair! You are "canned up" to silence! You generally get burned and cremated, as it costs too much to bury you in a dignified manner! Their hospitals and labs are centers of feudal physical and psychological damage and sicknesses and Inquisition!
Nobody has real true property! You pay tax for it, and it could be taken from you! THEY ARE CAPITALIST "CRAP"...!
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Transit of VENUS 05June2012 - midday - PST North America time

Details at: http://abiteinthechunk.blogspot.com/2012/03/transit-of-venus-tue-05-june-2012.html
NEXT TRANSIT 2117 December 10–11; Was the Mayan Calendar right ? Well as the 2012 Venus Transit it sure was !

Rover Curiosity

05 april 2012 - if nasa could prove to us this is real all the world would be folowing this in BEWILDERMENT...! [ http://abiteinthechunk.blogspot.ca/2012/04/truth-bewilders-most-of-us-hoax-is-very.html]

Based on: For Civil Control you cannot use illegal detentions extra Judiciary, and apply medication obliged alleged correctives, forced injections, and no two parties confrontation in Court...! The judge's first line is a Peace bond or legal reprimand; then community services...! Finally some time detention...! But mental health is very specific and not anybody's panacea of Catholic penitence for sins or INQUISITION court, given solely to a party with 'biased" interests: A psychiatric worker MD will not give a "un-biased" "firm" verdict...! THE REASONS FOR MY DETENTIONS, were mere ridiculous situations of self defense...! THE SYSTEM DOES NOT PROVIDE a timely 48-76 hrs "SELF DEFENSE" with their Mental Health system! Lawyers cost too much, and a Lower Civil Court is not present nor accessible...! THEY ARE DETERMINED TO CHASTISE YOU as a "child"...! YOU CANNOT BE MENACED to have obliged house detention medication injections and ingestion! TWICE I WAS "EXTRACTED" FORCEFULLY IN HAND CUFFS for this FROM my two places of "abode", without a "Court Order"!. Somehow on this one Canada is out of their minds...!

___________________________________________NO GO: CROWN-GOVERNMENT WOULD WIN...! They are the Illogic, war time heroes...! AND I WOULD BE CHARGED EXORBITANT DEBT OF a Un-just Justice too costly, so that it is not real justice for all!

I HAVE ALL FILES for History Justice to do Justice...!

Files will be given to the UNITED NATIONS, THE "HAGUE", HUMANS RIGHTS INTERNATIONAL, etc...!

I was forced fed sometimes until I was 3 years OLD...! But never Legally after, can anybody oblige me to take anything, much less to be pinned down for a "injection"...!

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IF I AM NOT WRONG you have more public rights and freedoms in Cuba...! Well you do in Venezuela...!

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Best Countries in the World - Europe of Course!

Inequality HDI [Human Development Index] by best Countries in the World!

DEDICATION to the Honorable Jack Layton - NDP Canada

DEDICATION to the Honorable Jack Layton - NDP Canada
DEDICATED to Jack Layton the only Canadian "Jesus" that I know of these years 2000-2011! He was promoting Government housing for years! He would go to Parliament Hill on a bike, so they attacked his health!
...A "capitalism" and to JACK LAYTON of the NDP Party! R.I.P. = you will not suffer anymore humans destruction...!
http://abiteinthechunk.blogspot.ca/2013/03/a-capitalism-and-to-jack-layton-of-ndp.html

ARE THESE NUMBERS OF WORLD STATISTICS OF A "rational" humanity ?

World "food" Facts

DO YOU THINK THESE NUMBERS REPRESENT A "RATIONAL" WORLD, "RATIONAL" GOVERNMENTS, AND MOSTLY ALL "IRRATIONAL" HUMANS ???

IS IT "RATIONAL" OR "NORMAL" FOR HUMANS TO DIE OF HUNGER ?

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CANADA: A country with other "countries" inside! Plenty of limited help for your medicals! But still used as a cover of worse issues! LIVING SOMEWHAT HAPPILY AS THE ONLY PhD in PURE LOGIC and Publisher! [Not much better than Venezuela if I became forcefully a peasant !]. U.S.A is worse, but "publishes" my Books, with "Copyright"! [******There is nothing much worse than to be ignored and that your value and basic rights be denigrated!******]